Pregnancy and opk

Can I be pregnant and still get my usual results on opks? I took a look the second day after my period and it was dark like it is when I have a positive opk we had sex the day before. And I got another positive opk day before yesterday it's fading again now. And I have been feeling weird I also spotted and had do Make a visit to the er due to an extreme dizzy spell which turned out to be dehydration. Is pregnancy a possibility?